Grinding machine



June 4, 1929. J. N. HEALD ET AL 1,715,550

GRINDING MACHINE Filed June 13, 1927 4 Sheets-Sheet l glwuemtou James X. Heeli- Roger N. H'mEcL Edward C). Tql Yor June 4;, 1929.

J. N. HEALD ET AL GRINDING MACHINE Filed June 13, 1927 4 Sheets-Sheet 2 Eon" June 4, 1929. I J. N. HEALD ETI' AL 1,715,550

' GRINDING MACHINE Filed June 13, 1927 4 Sheets-Sheet 3 June 4, 1929 J. N. HEALD ET AL GRINDING MACHINE 7 Filed June 15, 1927 4 Sheets-Sheet 4 gmmtm 'Jlmes N. Head,

Patented June 4, 1929.

UNITED STATES I 1,715,550 PATENT OFFICE.

JAMES N. HEALD, ROGER N. HEALD, AND EDWARD M. TAYLOR, 0F WORCESTER, MAS- SACHUSETTS, ASSIGNORS TO THE HEALD MACHINE COMPANY, OF WORCESTER, MASSACHUSETTS A. CORPORATION OF MASSACHUSETTS.

enmnme Application filed June 13,

The present invention relates to automatic I grinding machines, of the type employed for surface grinding, and more especially wherein the faces of successive small flat articles, such as piston rings, Washers, ball races and the like, are sub ected to the action of a grinding wheel. More specifically, the invention relates to that class of grinding machines disclosed, for example, in the patent to Littman, No. 1,361,883, granted December 14, 1920, and the patent to Law, No. 1,582,481, granted April 27 1926, wherein the workpieces, stacked in a magazine, are successively transferred to the grinding position and ultimately discharged from the machine by the intermittent rotation of a work carrier plate.

. The invention contemplates improvements in mechanism of this class, including an accurate driving mechanism for the work carrier, and one that will subject the arts to no a preciable strain. Means are a so provide to locate each successive workpiece very accurately on the revolving chuck, which is used to hold the work in grinding position.

Another object of the invention is to prevent the formation of scratches on the under face of the workpiece (which in a great many cases have already been finished) said scratches resulting, in prior machines, from the rotation of the work carrier under the bottom workpiece, which presses heavily against said carrier due to the combined weight of all the articles in the magazine. To that end the invention provides means to hold the stack of articles firmly in the magazine, and to lift them slightly above the level of the carrier, except at such times when the carrier is stationary and the lowermost workpiece is free to drop into the pro er conveying aperture of the carrier. Accor ing to the invention, the pressure employed to grip the articles during this lifting action, is limited to what is necessary for the purpose, in order that the articles may not be deformed.

The above and other advantageous features of the invention will-hereinafter more fully appear, reference being bad to th' panying drawings, in which- 'Fig. 1 is a side elevation ofa grinding machine, built in accordance with the invention, certain parts being broken away to show the construction of the novel mechanism.

Fig, 2 is a fragmentary front elevation, ceraccom- MACHINE 1327. Serial No. 198,484.

tain parts being removed, showing a cam that controls the magnetic chuck circuit.

Fig. 3 is a detail sectional view, on an enlarged scale, of the actuating mechanism for the work carrier, the section being taken on the line 33 of Fig. 2.

Figs. 4, 5, 6 and 7 are sectional views taken respectively on the lines 44, 5-5, 6-6, and 77 of Fig. 3.

Fig. 8 is a developed view of the work carrier actuating cam.

Figs. 9 and 10 are respectively front and side elevations of the work holding magazine and the mechanism to lift the stack of workpieces in said magazine, these parts being shown detached from the machine.

' Fi 11 is a fragmentary plan view, showing t 1e automatic chuck-elevating feed that colnplensates for the wear of the grinding ee v 1 Fig. 12 is a front elevation of the parts shown in Fig. 11. I

Fig. 13 is an enlarged fragmentary View of certain arts shown in Figs. 11 and 12.

Fig. 14 IS an enlarged sectional view taken on the line 14-14 of Fig. 11.

Fig. 15 is a vertical sectionalview taken on the axis ofthe magnetic chuck, and showing the chuck driving and elevating mechanisms. Y

' Fig. 16 is a fragmentary elevation of the left hand side of the machine, showing a cam operated valvemechanism that controls the operation of the work carrier.

Fig. 17 is a fluid pressure or piping diaram.

Fig. 18 is a plan view of plate.

Figs. 19 and 20 are diagrammatic'views showingthe stack lifting operation.

Like reference charactersrefer to like parts throughout the drawings.

Referring first to Fig. 1, the machine is mounted one base 1 which provides ways,

not shown, for the horizontal reciprocation .and adjustment of a carriage or table 2.

head 4. The grinding wheel 5 is carried by p the head 4, being mounted on a spindle 6 which is journalled in said head. The grinding wheel may be rotated in any, suitable manthe work carrier.

ner; as shown in broken lines in Fig. 1,

the shaft 6 provides a drum 7, which is driven from a main drive shaft 8 by means of a pulley 9 on said shaft and a belt 10. To provide for the slight rise and fall of the head 4,

vidual workpieces to grinding position, and

the rotating magnetic chuck, which holds and rotates the workpiece in said position, are

all carried by a separate machine unit 11, which is mounted for vertical adjustment with respect to the base 1, on slidways 12, a hand wheel 13 being provided to raise or lower the unit 11 at will. As shown in F lg. 15, the magnetic chuck 14 is mounted on the top of a spindle 15, which is carried in bearings 16 and 17 provided by the unit 11; said chuck 14 and spindle 15, as in the case of the wheel 5 and spindle 6, may be rotated in any suitable manner; the drive shown being obtained through a worm wheel 18, fastened to the spindle 15, that meshes with a driving worm 19, the latter being mounted on a shaft 20 which, as indicated in dotted lines in Fig. 1, ultimately derives its'rotation from the aforesaid main drive shaft 8. A universal joint 21 is provided to maintain the drive despite relative vertical adjustment of the unit 11.

The machine of the present invention, in common with that disclosed and claimed in a copending application of Heald and Law, Serial No. 84,881, filed January 30, 1926, contemplates an inclined reciprocatory motion of the head 4, whereby to bring the grinding wheel down upon the surface of the rotating workpiece with full face contact. As in said Heald and Law machine, the grinding wheel 5 travels downwardly, for the grinding of each successive workpiece, to a definite level, so that each workpiece may be ground to the same depth; this necessitates the timing of the work carrier mechanism, to transfer successive workpieces to grinding position, in accordance with the motion'of the grinding head 4 on the inclined ways 3.

Still referring to Fig. 1, the driving means for the head 4 is herein shown as a motor 22 mounted on the carriage 2 which, by means of pulleys 23 and 24 and a belt 25 drives a shaft 26 at reduced speed. A worm 27 on the shaft 26 meshes with and drives a worm wheel 28 on a shaft 29. By means of a cam, not shown, carried on the shaft 29 the grinding head 4 is given its reciprocatory motion on the inclined ways 3, and this mechanism, as well as the adjustment means to control the depth of cut and to vary the length of time during which the head 4 dwells at its lowered position, need not be further described herein,

since it forms nopart of the present invention. Each reciprocation of-the head 4, for the reasons above stated, must be accompanied by a definite angular movement of the work carrier plate 30. Referring to Fig. 16, which shows the opposite side of the machine from that shown in Fig. 1, the shaft 29 provides a cam 31 at each revolution of which a cam portion 32 comes in contact with a lever 33, or a suitable roller 34 provided thereby. The lever 33 is pivoted at 35; at a point 36 spaced from the pivotal point 35 but on the same level, is pivoted an arm 37. The arm 37 is of the same length as one arm of the lever 33, and the ends of said lever and said arm are connected by a bar 38 which, as will be readily seen, must always be horizontal. This mechanism is provided because, as will hereinafter appear, the carriage 2 is preferably given a limited reciprocator-y traverse, and atall events it is adjustable longitudinally with respect to the base 1.

The bar 38, when depressed by theactionof the cam portion 32 acting through the levers described, moves a lever 39 pivoted at 40 on the machine base 1; the lever 39 is connected at 41 to a valve member 42 which causes fluid pressure actuation of the carrier 30.

As shown in the fluid pressure diagram of Fig. 17, fluid under pressure may be supplied from any convenient source, such as the pump 43. The fluid is led by a supply line 44 to the fluid entrance ort 45 of a valve casing 46 in which the va ve member 42 is located. .Fig. 17 although diagrammatic as to the relative position of the units in the fluid pressure system, shows the valve casing 46 in true section; said valve casing provides two chambers 47 and 48 at opposite ends thereof, these chambers being in communication with each other and with the fluid entrance port 45 by means of a passage 49. The valve cas ing 46 also provides chambers 50 and 51 ad jaeent the chambers 47 and 48, and a centrally located chamber 52. A continuous hole is made right through the casing 46, passing through all the aforesaid chambers, the valve member 42 being located therein. The member 42 is formed out of a cylindrical piece whose diameter is the same as the diameter of.

the hole through the several chambers. But

at 53 and 54 thediameter ofthe valve 42 is reduced; this leaves a central portion 55 0fthe main diameter. It follows that when the valve member 42 is in its normal raised position shown in Fig. 16, (where it is ordinarily maintained by means of a coil spring 40 surrounding the pivot 40 and connected to the base 1 and the lever 39, respectively) the chamber 50 is connected to the chamber 47, while the chamber 51 is connected to the chamber 52 and disconnected from the chamber 48. 'When the valve member 42 is de pressed, as described, the chamber 51 is connected to the chamber 48, and the chamber 50 "is connected to the chamber 52, and in this position the parts are shown in Fig. 17.

The chambers 50 and 51 connect, by means of flexible piping 56 and 57, respectively, to the opposite ends of a generally semi-circular chamber 58. The construction of said chamber isshown in Figs. 3 and 5 it is located, as shown in Fig. 1, in the unit 11, and a horizontal shaft 59 extends through it, the axis of the shaft being located at the center of the circle whose arcuate portion forms one boundary wall of the said chamber as it is seen in cross section. A sleeve 60 surrounds the shaft 59, and this sleeve extends thropgh the right hand wall of the chamber, as it is viewed in Figs- 1 and3. To this sleeve 60 is fastened in any suitable manner an arm 61, which contacts with the plane surfaces which form the side walls of the chamber and the outer end of which terminates in an arcuate portion of the same radius as the said circle and lies close to it, so as to allow free movement but prevent the free passage of fluid..

It will readily be seen that the chamber 58 is, in this manner, divided into two portions, and whenever the pressure fluid is made active, for example. by way of the piping 57 thereby to enter the chamber58 through the port 57 then the arm 61 will be rotated clockwise from the position shown in Fig. 5 to the position indicated in Fig. 17, the sectional view of the chamber 58 in the latter figure being taken looking in the opposite direction, while whenever fluid is admitted -via the port 56 through the piping 56, the arm will be rotated counterclockwise to the other extreme position.

The movement of the valve member 42, which is mechanically actuated in timed relation to the reciprocations of the grinding head 4 as described, is thus made use of to cause fluid pressure actuation of the arm 61; when the cam portion 32 acts to depress the valve member 42, the fluid flows from the pump 43, by way of the piping 44 and entrance port 45, to the chamber 48, thence past the reduced portion 54 of the valve 42 to the chamber 51, thence by the piping 57 to the port'57 The movement of the arm 61 forces fluid out of the chamber 58 by way of the port 56 whence, by the piping 56 and chan'iber 50, it passes the reduced portion 53 ofthe valve 42 and exits by means of piping 52 to the usuals'torage tankwhieh is provided in this class of machines for the fluid. Immediately thereafter, the cam portion 32 moves beyond the roller 34 on lever 33, and the valve member 42 is raised; this reverses. the direction of flow'of the fluid in the piping 56, 57 and moves the arm through 180 back to its original position, as will be readily apparent without further description. Thus for each revolution of the shaft 29 which controls the reciprocation of the head 4, the arm 61 is given a doublev oscillation through 180, and

this causes an angular movement of the work carrier plate 30, always in the same direction of rotation, aswill now be described.

On the sleeve 60, outside the chamber 58, is fastened a member 62, which therefore partakesof the angular motion of said'sleeve given it by the motions of the arm 61. The member 62 provides a radially extending portion 62 to which is pivotally attached at 63 a pawl 64. See Fig. 6. The pawl 64 is pressed by a spring 65 against a member 66, which has a pair'of ratchet notches 67, 67 cut in its periphery, said notches being 180 apart. Figures 3 and 6 should be compared in order to understand the relation of these parts. The oscillations of the member 62, therefore, turn the member 66 through 180 in a clockwise direction as viewed in Fig. 6,

which is a section taken looking to the right fastened to the shaft 59, as is likewise a cam' member 70 cut from a cylinder. It will be seen at each oscillation of the arm 61, the shaft 59 and the cam members 70 are turned exactly 180, always, however, in the same direction of rotation.

As shown in Figs. 1 and 3, the carrier plate 30 is supported on a stationary plate 71, which provides a recess 72 for the reception of the magnetic chuck 14, and another recess, not shown, for the discharge of the finished workpieces. ported by three rods 71 inserted in bosses on the underside thereof, the other ends of said rods being inserted'in three bosses, which are part of the stationary unit 11, and rest on three set screws 71*, for the purpose of adjusting the height of the. plate to suit the chuck. A boss 73 formed in the stationary frame of the unit 11 acts as a guide for the hub of a disc 75, said hub having a vertical shaft 74 slidably keyed therein for the purpose of being readily adjustable to suit va rious thicknesses of, transfer plates. The disc 75 is best shown in Figs. 3 and 7, and provides four rollers 76 projecting from its The plate 71 is suplower side, these rollers being spaced 90 ably', four ring-like inserts 77, each one have mg an aperture 78 for the reception of the workpieces. By simply replacing the inserts 77 with others providing different sized apertures, any size of round workpiece (within limits, of course) can be handled. The workpieces are stacked between three posts 79, 80 and 81, which constitute a magazine. As the carrier plate revolves, the workpieces drop into the apertures one at a time being supported by the underlying stationary plate 71; the workpieces are thus moved one station at a time, being ground when they reach the magnetic chuck which is located, as aforesaid, at the recess 72; finally, being moved off of the magnetic chuck, they are discharged through a hole in the plate 71. The foregoing cycle of operation will be found described in the patent to Littman referred to, but is briefly recapitulated in order that the present invention may be better understood.

Referring to Figs. 1, 9 and 10, the magazine is lifted before each turning movement of the carrier 30; to accomplish such lifting, the post 80 is pressed in the direction of the posts 79 and 81, thus gripping all the workpieces in the magazine. The amount of the gripping force is dependent on the weight of the magazine including its con-' tents, and thus when there is, for example, but one thin walled workpiece left in the magazine, it will not be distorted by the pressure, while when there are a great many heavy workpieces in the magazine, the pressure will be adequate to hold their combined weight. The foregoing is embodied-in the following mechanism The shaft 59 has a cam '82 fastened to it, the position of which longitudinally on said shaft may be best seen in Fig. 1. Referring now to Figs. 9 and 10, the cam 82 is generally circular, but at the extremities of a diameter, the cam is flattened forming parallel chord portions 83, 83. A lever 84, pivoted at 85 on the unit 11, provides a roller 86 in contact 7 with the cam 82; the lever 84 also provides an inclined portion 86' the purpose of which will presently appear.

All three of the posts 79, 80 and 81 are held by brackets 87, 88 and 89, respectively.

- These brackets are adapted to hold the posts at'any height desired, set screws being provided for the purpose. The brackets do not completely surround the posts, but are cut away on the inside; thus the posts alone, and not the brackets, contact with the workpieces. The brackets 87 and 89 which hold the posts 79 and 81 are adjustably fastened to a member 90, which is pivoted at 91 to the stationary cover plate92 (provided for the purpose of excluding dirt), which forms part of the unit 11. The member 90 provides a boss 93 in which is mounted a vertical pivot stud 94:. Two lever arms 95 and 96, are mounted on this stud, the arm 95 serving to hold the third bracket 88. The arm 96 provides an adjusting screw 97 which is adapted bottom of the lever 101 is a roller 102, which,

when the cam surface 86 is raised, is pressed outwardly thereby, thus rocking the lever 101 clockwise, Fig. 10. The upper end of the lever 101 contacts with the lever arm 96, and when the lever 101 is actuated as described, the arm 96 is therefore moved to the right, Fig. 10; the latter, in turn, exerts a similar turning movement on the lever 95, directly through the screw 97. The bracket 88 and the post 80 are thus pressed towards the posts 7 9 and 81, and this action clamps. the workpieces in the magazine. WVhen all three posts are contacting the workpieces, there can be no further relativemovement between them, and further movement of the lever 101 serves to turn the whole magazine unit about the pivot 91 of the member 90. It will readily be seen that the pressure of the posts against the workpieces is proportionate to the weight of allthese magazine parts, including the weight of the workpieces in the magazine, for the upper end ofthe lever 101 exerts more and moreclamping force as it is moved until the reaction becomes substantially equal -to the force exerted at the roller 102, due to the combined weight acting around the pivotal point 91 (the two arms of the lever 101 are substantially equal in this embodiment of the invention) when this equality is obtained the magazine unit lifts. The action is shown diagrammatically in Figs. 19 and 20.

When the shaft 59 is stationary, the cam 82 is in the position shown in Fig. 9, and the bottom workpiece is consequently free and drops into the appropriate aperture 7 8 provided in the work carrier plate 30, for, of course, the carrier cannot be moving when the shaft 59 is stationary, which is most of the time. But as the shaft 59 starts moving, the super imposed workpieces in the magazine are lifted off of the workpiece which is moved by the carrier plate, and in order that this lifting action may occur before any appreciable movement of the plate occurs, the screw97 is tightened to allow practically no clearance between the posts and the workpieces; thus,

the instant the shaft 59 and cam 82 start to move, said workpieces are gripped and lifted. Referring to Figs. 2 and 3, the shaft 59 also has fastened to it-a cam 103 which conmmeeo box like structure 106 is a switch member 107. The pivot shaft 105 extends outside the box 106 and is surrounded" by a coil chuck must be de-energized when the car rier is moving and energized when the workpiece is being ground, and this is accomplished by controlling the chuck from the shaft 59 which controls the movement of the carrier.

Although the mechanism so far described is complete it itself and suflicie'nt for the automatic grinding of round workpieces which are stacked in the magazine, it is nevertheless desirable to cause the grinding wheel 5 to be given a slight horizontal traversing. motion so that a groove will not be worn in the said wheel. For that purpose, a pair of adjustable reversing dogs 111 and 112 are mounted on the carriage 2, being positioned to strike a reversing member 113 and thus reverse the direction of travel of the table 2. The reversing member 113 is connected to a valve member 114 which may be seen in the fluid pressure diagram of Fig. 17, the parts connected with said reversing valve 114 being shown in true section in this figure. It is not necessary tofurther describe the fluid pressure mechanism which, responsive to the movement of the valve- 114, tranverses the table 2 back andforth,

as such mechanism is well known in machines ofthisclass.

Inorder to keep the wheel 5 sharp and tsue, provision is made fordressing it'periodically. As shown in Fig. 1, a dressing device 115 is.

' mounted in the unitll and partakes of the vertical movements of adjustment of said unit. The device 115 is, of course, independently adjustable, and is carried in a threaded member 116 for that pu ose. The left hand table dog 111, instead 0 being a fixed dog, like the right hand dog 112,- is pivotally mounted and capable of beinglifted, either manually or automatically, above the end of the reversing lever 113. When so lifted, the table 2 undergoes amplified movement to the right, thus carrying the grinding wheel 5 est the dressing device115 which is. located in its path of movement; thus said wheel is dressed and 'trued. Prior to contact between the grinding wheel and the dresser, however, the unit is automatically raised by a small amount, thus insuring a substantial contact between said wheel and dresser. As shown in Fig. 1, a cam member 117 adjustably attached.

to the table 2 is' adapted to enga e and deiessaroller-llS carried on t e end of a lever 119. The lever 119 is connected to another lever 119 which, by means of a link 120, operates a pawl 121. Referring now to Figs. 11 to 14 inclusive, the pawl 121 is carriedon the end of a short shaft 122, which pivotally connects the link 120 to an arm 123'journalled around the shaft. 124, to which the hand wheel 13 is attached. The shaft 122 provides a pin 125 located back of the link 120, said pin contacting with an adjustable guide member 126, by means of which the pawl can be caused to move a ratchet wheel 127 a variable amount. These parts are best seen in Fig. 13. As shown in the sectional' view of Fig. 14, a spring pressed plunger 128, pressing against a flat portion of the shaft 122, causes the pin 125 to follow a stud 129 carried by the guide member 126.

The ratchet wheel 127, is thus turned through an angular distance which is adjustable, and as the ratchet wheel 127 is attached to'the shaft 124, the latter is turned. The

shaft 124 can be seen in Fig. 15; it carries a worm 130 which meshes with a helical gear 131 on a vertical screwshaft 132. The latter passes through an internally threaded member 133 that is fastened to the unit 11,.

and thus when the shaft 132 is turned, the unit 11 is raised.

Raising of the unit A device 115, but inasmuch as the magnetic chuck 14 is raised by an equal amount, the

relation between the lower part of the periphery of the wheel 5 and the chuck 14 will not be changed, and the workpieces will be groung to a fixed and predetermined size. This ressing operation can be performed more or less frequently, depending on ,the accuracy with whichthe workpieces have to be ground. It seems scarcely necessary to observe that the motor 22, mustbe stopped during the dressing, in order thatthe head. 4

have provided a greatly improved drivefor the work carrier plate and an eifectual means of preventing detrimental scratches 1n the already ground surfaces of the workpleces. In the developed cam surface as shown 1n Fig. 8, it will be noticed that the path of the cam 70 is so formed that a portion 134 of it gives the appropriate roller a 'slight rotary motion in advance of its being. taken up by theclosed path 135. Also,-referrin to Fig. 5, the arm 61 ,rovides a plug 136 w 101! extends on both sides thereof, and is adapted to partially close the .respective ports 56 and 57. whichever one is, at that ,moment, the fluid exit port, and thus the movements of the work carrier actuating mechanism are ac- 11 raises the dressing I mag be at its bottom position, the motor being;

'complishe'd without jar. It will be noted also,

to say, gentle acceleration and possibility of accurate timing.

The mechanism whlch lifts the magazine and prevents scratches on the ground surfaces of the workpieces operates to force the posts 79, 80 and 81 together with a certain minimum force which isnot suflicient to deform even thin walled workpieces; as the magazine is filled up, the force is increased in a definite ratio to the weight of the articles in the magazine, but the holding pressure is, under such circumstances, resisted by not one but many workpieces. Similarly, heavy workpieces will be gripped with a greater force in order to hold their weight, it being obvious that they can withstand such a greater force without "deformation.

We claim:

1. In a grinding machine, the combination with a magazine for holding a stack of articles to be ground, and a carrier plate be low said magazine to transfer the articles one by one, to a position where they may be operated upon by a grinding Wheel, of means for lifting the magazine when the carrier plate is operated.

2. In a grinding machine, the combinatlon with a magazine for holding a stack of articles to be ground, and a carrier plate below said magazine to transfer said articles, one by one, to a position where they may be operated upon by a grinding wheel, of means for lifting all but the bottom article in the.

magazine while said bottom article is being moved by said carrier plate, in order to prevent scratching of said articles by said plate.

3. In a grinding machine,-a plurality of posts comprising a magazine for a stack of articles, an intermittently rotating carrier plate to transfer said articles, one by one, to a chuck for a grinding operation, and means for urging said posts towards each other while said carrier plate is moving.

4.. In a grinding machine, a plurality of posts comprising a magazine for a stack of articles, an intermittently rotating carrier plate to transfer said articles, one by one, to a chuck for a grinding operation, means for forcing said posts together while said carrier plate is moving, and means for causing said force to be approximately proportionate to the weight of the stack of articles.

:5. In a grinding machine, a plurality of posts comprising-a magazine for a stack of articles, an intermittently rotating carrier plate to transfer said articles, one by one, to a chuck for a grinding operation, means for forcing said posts together while said carrier plate is moving, and further means for lifting said posts, whereby the stack of articles may be held by the magazine and lifted from' the carrier plate to prevent scratching of the bottom article.

6. In a magazine for grinding and like machines, a plurality of posts, a common support for said posts, a pivotal mounting for said support, said pivot lying outside the area enclosed by said posts, one or more of said posts being movable relative to the other or others, and means for pressing the movable post or posts toward the other or others, the point of pressure being located above the plane of the aforesaid pivot, whereby articles in said magazine are first held by said magazine and then lifted.

7. In a grinding machine, the combination with a magazine and a carrier plate for transferring articles successively to a grinding position, of intermittently operating mechanism for operating said carrier plate, and fluid pressure operating means for operating said intermittently operating mechanism. i v

8. In a grinding machine, the combination with a magazine and a carrier plate for-trans ferring articles successively to a grinding po-' sition, of a vertical shaft to which said carrier is attached, a member carrying a plurality of projecting elements also attached to said shaft, a cylindrical cam fitting between two of said projecting elements, and

' means for intermittently rotating said cam,

whereby to shift said carrier plate.

9. In a grinding machine, the combination with a magazine, a magnetic chuck and a carrier plate for transferring articles successively to said chuck, of a rotor, means for intermittently oscillating said rotor, means for transferring said intermittent oscillatory movement to intermittent unidirectional actuation of said carrier plate, and means also under the control of said rotor for energizing and de-energizing said chuck.

10. In a grinding machine, the combination with a magazine and a carrier plate for transferring articles successively to a grinding osition, of a rotor, means for intermittent y oscillating said rotor, means for transfer-ring said intermittent oscillatory movement to intermittent unidirectional 'actua tion of said carrier plate, andmeans also under the control of said rotor for periodically lifting the articles in said magazine.

, 11. In a grinding machine, the combina tion with a magazine, a magnetic chuck and a carrier plate for transferring articles successively to said chuck, of a rotor, fluid pressure ,means for intermittently oscillating said rotor, means for transferrin said intermittent oscillatory movement to intermittent unidirectional actuation of said carrier plate, and means also under the control of said rotor for energizing and de-energizing said chuck. e y 12. In a grinding machine, the combination with a magazine, and a carrier plate for transferring articles successively to a grinding position, of a rotor, fluid pressure means for intermittently oscillating said rotor, means for transferring said intermittent oscillatory movement to intermittent unidirectional actuation of said carrier plate, and means'also under the control of said rotor for periodically lifting the articles in said magazine.

13. In a grinding machine, the combination with a magazine and a carrier plate for transferring articles successively to a grinding position, of a cylindrical cam, projecting elements connected to said carrier plate, sai elements fitting between surfaces on said cam, whereby said carrier plate is positively controlled by movement of said cam, and mechanism adapted to move said cam always to a given position.

14. In a grinding machine, the combination with a magazine and a carrier plate for transferring articles successively to a grinding position, of a cylindrical cam, projecting elements connected to said carrier plate, said elements fitting between surfaces on said cam,

whereby said carrierplate is positively controlled by movement of said cam, ratchet and pawl mechanism to actuate said cam, and a spring pressed member cooperating with notches to insure the movement of said cam always to the. same position.

15. In a grinding machine, the combination with a magazine and a carrier plate for transferring articles successively to a grinding position, of oscillatory actuating mechanism for said carrier plate comprising a semicircular chamber, an arm therein, and means for admitting fluid under pressure first to one side and then to the other side of said chamber. v

16. In a grinding machine, the combination with. a magazine and a carrier plate for transferring articles successively to a grinding position, of oscillatory actuating mechanism for said carrier plate comprising a semicircular chamber, an arm therein, means for admitting fluid under pressure first to one side and then to the other side of said chamber, and fluid pressure cushioning means whereby said carrier plate is moved without shock.

Dated this 6th day of June, 1927.

JAMES N..HEALD. ROGER N. HEALD. EDWARD M. TAYLOR. 

